Hello Iceberg,I had the same issue just few hours ago, the problem is
that superfish-vertical.css is applied before superfish.css when you
use response.files.append() and overwrites some css styles.
One solution could be editing the /view/layout.html adding the
superfish-vertical.css after. In 43 line
{{#------ require CSS and JS files for this page (read info in
base.css) ------}}
{{response.files.append(URL('static','css/base.css'))}}
{{response.files.append(URL('static','css/superfish.css'))}}
{{response.files.append(URL('static','css/superfish-
vertical.css'))}}
{{response.files.append(URL('static','js/superfish.js'))}}
{{#------ include web2py specific js code (jquery, calendar, form
stuff) ------}}
Remember delete
response.files.append(URL(request.application,'static','css/
superfish-vertical.css')) from your controller.
Tested and works fine.